This submission is an amended competing continuation application for MH56888, now titled "Interpersonal Functioning in Borderline Personality." The overall goal is to characterize the interpersonal functioning of patients with borderline personality disorder (BPD) in greater detail and with greater clinical relevance than has been done previously. A conceptual hierarchy of interpersonal functioning in BPD will be examined, ranging from long-term patterns of relatedness to moment-to-moment interpersonal appraisals, and the construct and predictive validity of these measures will be tested. The first specific aim is to characterize the adult attachment styles of BPD patients using multiple measures. The second specific aim is to undertake a detailed assessment of the interpersonal functioning of these patients in the areas of romantic relationships, friendships, and work using a state-of-the-art interview, the Revised Adult Personality Functioning Assessment (RAPFA). The third specific aim is to document that both attachment styles and patterns of relatedness identified with the RAPFA are associated with actual day-to-day interpersonal functioning; for this purpose, a Social Interaction Diary, adapted from the Rochester Interaction Record, will be used. At the most detailed level of analysis, the fourth specific aim is to undertake an assessment of social cognition in BPD patients using a paradigm evaluating biases in the perception of neutral human faces. The research will be conducted with three groups (N = 50 in each group): Patients with BPD and two comparison groups-patients with avoidant personality disorder (AVPD) and patients with no PD, i.e., those with an Axis I mood or anxiety disorder only. All patients will be assessed at intake and followed prospectively for six months. The accomplishment of these aims will be important not only for establishing the construct and predictive validity of these interpersonal variables in BPD but also for promoting the development of improved treatments on behalf of patients who suffer from this disorder. Identification of interpersonal risk factors will help achieve the long-term goal of not only knowing these patients well but also using this knowledge in sc ce-based therapies to improve their lives.